The Heartland Institute, which receives hundreds of thousands of dollars from the fossil fuel industry, including Koch Industries, rightly came under criticism this week for its secretive role in promulgating anti-climate change science.

Just last month the American Enterprise Institute (AEI) released a new series attacking the renewable energy industry. AEI has received at least $11.8 million from the fossil fuel industry, including Koch Industries, according to public IRS 990 forms recently obtained via Media Matters’ Conservative Transparency.

When you look at AEI’s funding and relationships, you see a clear connection to fossil fuels that never gets mentioned in their reports.

Here is a list of their funding relationships:

AEI has received at least $150,000 from Koch Family Foundations (tied to Koch Industries).

The President of AEI, Arthur Books, and Fellow Peter Wallison, coordinated (.pdf) political strategy with the Koch brothers, and presented on the “threat” of unions at the Koch conference in Aspen.

The author of AEI’s three part series was previously a Senior Fellow at the Manhattan Institute, which has received $6.7 million from the fossil fuel industry.

There is a clear pattern of fossil fuel companies and foundations spending millions of dollars propping up climate change deniers as part of a communications investment that protects their bottom line.

This shrewd investment appears to not be limited to creating questions about the scientific fact of global warming but also to create doubts in the minds of the public and policy makers about renewable energy. Renewable energy, the main market competitor to the fossil fuel industry, is rapidly approaching grid parity. Grid parity means that alternative or clean energy electricity is an affordable alternative to fossil fuels.

Therefore, it makes sense that the fossil fuel industry would invest in a communications infrastructure to discredit, weaken or even eliminate their competitors in the renewable energy industry.

Last week, the Checks & Balances Project confronted another fossil fuel-funded pundit, Robert Bryce, about his funding from the industry. Like the Heartland Institute and AEI, he refuses to disclose his connections to the fossil fuel companies he supports.

The Heritage Institute, AEI, and Robert Bryce’s employer the Manhattan Institute, are all part of a growing echo chamber of fossil fuel-funded public relations infrastructure. But these think tanks want to hide their ties to the industry because the more the public learns about their ties to fossil fuels, the less they are viewed as credible messengers on the energy debate.

These same think tanks were used to confuse the public on the health risks of smoking and are now being used to dismiss the science of climate change and the meteoric growth of renewable energy technologies, all without disclosing their ties to the industry.

The Checks & Balances Project will continue to monitor and expose this misinformation echo chamber distorting the energy debate.